The knight sky hook measures 21.25"H. Gadgets inspired by science were popular in Victorian times. People loved demonstrations of the seemingly impossible. Optical illusions, magnetic forces, the laws of gravity, all seemed magical in an era when society was changing fast and the industrial revolution was unstoppable. Skyhooks could be set on a shelf or the rim of a table and set in motion to everybody's delight and amazement. Made in recycled metal sheet, cut by hand using original templates. Hand painted in great detail, finished in aged patina, waxed. Counterweight is calibrated to create swing.